Residual Anti-pneumococcal Immunity After Pneumococcal Immunization in ANCA-associated Vasculitis

Assistance Publique - Hôpitaux de Paris19 enrolled

Overview

Descriptive study of the residual anti-pneumococcal immunity in patients with Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) who have previously gone through pneumococcal immunization.

The purpose of this study is to determine, through serotype-specific enzyme linked immunosorbent assay (ELISA) and opsonophagocytosis (OPA) titres whether AAV patients who have gone through pneumococcal vaccination are protected against invasive pneumococcal diseases (IPD).

Study Type

OBSERVATIONAL

Enrollment

Conditions

Pneumococcal Infection ANCA-associated Vasculitis

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Age ≥ 18 years * Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis: diagnosis for granulomatosis with polyangiitis, microscopic polyangiitis or eosinophilic granulomatosis with polyangiitis according to American College of Rheumatology criteria * Anti-pneumococcal immunization in the past 36 months * History of anti-pneumococcal vaccination according to French recommendations (simple vaccine schedule with PPV23 or combine vaccine schedule with PCV13 followed by PPV23 8 weeks later) Exclusion Criteria: * Known or suspected pregnancy * Splenectomy * Patient without social security coverage * Patient opposal

Locations (1)

AP-HP ; Cochin Hospital

Paris, Île-de-France Region, France

Outcomes

Primary Outcomes

Residual anti-pneumococcal immunity after pneumococcal immunization.

Proportion of patients at baseline (V0) with ≥1 µg/mL ELISA immunoglobulins G (IgG) antibody titers to at least 6 of the 10 shared serotypes (i.e. 3, 4, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F) included both in the 13-valent conjugate pneumococcal vaccine (PCV13) and in the 23-valent non-conjugate pneumococcal vaccine (PPV23)

Time frame: visit V0 (day 0)

Secondary Outcomes

To assess serotype 3, 4, 6B, 7F, 9V, 14, 18C, 19 A, 19F, 23F, 10A and 12F-specific residual immunity after vaccination

ELISA specific antibody titres to serotype 3, 4, 6B, 7F, 9V, 14, 18C, 19 A, 19F, 23F (included both in PCV13 and PPV23), 10A and 12F (specific to PPV23)

Time frame: visit V0 (day 0), visit V-1 (pre immunization)

For each of the following serotypes (3, 4, 6B, 7F, 9V, 14, 18C, 19A, 19F, 23F), to assess among ELISA-protected patients (i.e. with a ≥1 µg/mL ELISA IgG antibody titer) the proportion who also show in vitro opsonophagocytic antibody activity

Descriptive analysis: a/ For each of the following serotypes (3, 4, 6B, 7F, 9V, 14, 18C, 19A, 19F, 23F), opsonophagocytosis (OPA) titers will be measured in ELISA-protected patients at V0. Opsonophagocytic antibody activity is considered positive if the antibody titer is above a serotype-specific predefined threshold. B/ The proportion of overall OPA-protected patients (meaning ≥ 50% of OPA positive serotypes )

Time frame: visit V0 (day 0)

For patients for whom pre-vaccinal serum is available (via the PHENOVASC bank), to assess the impact of immunization on serotype-specific ELISA antibody titer and OPA activity.

For patients already included in the PHENOVASC study (V-1) ≤6 months before receiving pneumococcal immunization, anti-pneumococcal immunity will be assessed for serotype 3 , 4 , 6B, 7F, 9V, 14 , 18C, 19A , 19F , 23F, 10A and 12F (with ELISA only for the two latter). For each serotype: In ELISA, we will describe the proportion of responding patients (i.e. with a two-fold increase from V-1 to VO and a ≥1 μg/ml titre at V0. In VO ELISA-responding patients, OPA titers will be measured. An opsonophagocytic antibody activity is considered positive if the antibody titer shows a four-fold increase from V-1 to V0 and is above a serotype-specific predefined threshold.

Data from ClinicalTrials.gov

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